Flash-light battery.



M. E. HOLMES.

. FLASH LIGHT BATTERY.

APPLICATION FILED MAR. 2. 1914.

WIT/158.958 I IIIVVENTOI? W MAJEIR E. HEILMEE A TTOR/VEY UNITED STATES PATENT OFFICE.

MAJOR E. HOLMES, F LAKEWOOD, OHIO, ASSIGNOIR, BY MESNE ASSIGNMENTS, TO NATIONAL CARBON COMPANY, INC.-, A CORPORATION OF NEW YORK.

FLASH-LIGHT BATTERY.

Specification of Letters Patent.

Patented Apr. 30, 1918.

Application filed March 2, 1914. Serial No. 822,002.

To all witom it may concern:

Be it known that I, MAJOR E. HOLMES, a I

and useful. Improvement in Flash-Light Batteries, of which the following is a full, clear, and exact description.

This invention relates to the combination of a flashlight battery with a rheostat, preferably in the form of a pile built up of a plurality of thin disks. The resistanceof such a pile rheostat may be varied, in the usual manner by adjusting the pressure applied thereto. I

In flashlight batteries as well as in all other dry cell batteries it is wellknown that the E.M.F. of a single cell decreases a great deal during its use. Cells having an initial of from 1.5 to 1.6 volts are serviceable until the voltage drops to below g volt. In fact, the majorportion of the period of service of such batteries occurs at voltages considerably below an of 1 volt. In selecting the lamp to be used in such batteries it is therefore practicable to design it, not forv utilization at the initial or final voltage, but at some intermediate point. For instance, a battery composed of threejdry cells each having an initial of 1.5 to 1.6 volts i known as a 4 volt battery and is accordingly used with a 4 volt lamp. From this it will be evident that the incandescent lamp is subjected to a consid-' down the excess in the first part of the cell life. In addition to prolonging the usefulness of the combination,I also find it.

advantageous to be able to readily vary the illumination produced. By use of the simple device shown in the accompanying drawings, I am able to quickly and'uniformly vary the quantity of light by adjusting the pressure upon the rheostat.

In the drawings:

, Figure 1 shows cross section View of a combined lamp, casing battery and rheostat. b Fig. 2 i a modified form of contact mem- Fig. 3 is a further modification. Fig. 4 is a battery with a rheostat as a single unit.

Fig. 5 is a modification of the battery of Fig. 4.

Fig. 6 shows the modification in Vertical cross section of my invention adapt d for use with a'vest pocket battery.

Fig. 7 is a further modification of the type shown in Fig. 6. I a

Referring to Fig. 1 which is illustrative of one completed development of the idea, the flashlight consist of a cylindrical metal casing 1 having a lining 2 of heavy paper or some other insulating material. One end of the metal tube is screw threadedto receive a metal cap 3 having a central projection 4. The dry cells 5, 6 and 7 are placed in series in the tube, contact being made between the adjoining cells through the bottom 8 of the zinc container and a projection 9 of the car;

bon electrode. To'the open end of the cas which I place in one form between the carbon 9 of the dry cell 7 and'the base 17 of the lamp. The compression rheostat consists of an insulating tube 18 containing a plurality of thin disks 19. The disks are preferably, though not necessarily made of carbon plates which have a high contact resist.- ance depending upon the} pressure and are particularly well adapted for this purpose.

The complete circuit of the flashlight then stat 16, lamp 12, reflector 11, nipple 10, casing 1, cap 3 and is closed through the contact land zinc bottom 8.

Itvi ill be evident that the vcontact is closed by screwing the metal cap 3 on the Teasing 1.

consists of the three cells 5, 6, 7, the .rheo- Further adjustment produces a Variation in the pressure on the rheostatwhich will vary the resistance to produce the results previously described.

In Fig. 2 pressure is applied to the rheostat by manipulating the push button con tact 20 placed in the end of the cap. An insulating washer 21 is inserted in the casing and a light spring 22 may be used to keep the batteries together with the desired maximum resistance. The push button is re turned by means of a spring 23.

Figs. 3, 4, 5, show various Ways of placing theirheosta't in the casing. In Fig. 3 it is placed at the same end as the cap, and is contained in an insulating casing 24"having a rim 25 at each end to hold the disks in place. One advantage of placing the rheostat at the bottom adjacent the push button is thatpressure can be applied thereto without moving the cells in the casing.

In'Figs. 4 and 5, the rheostat is perma- I nently fastened to the carbon 26 of the dry cell and sealed therein by means of the pitch seal 27. A pin 28 attached'to the bottom of the zinc container 29 makes contact with the. rheostat of the adjoining cell through an opening 30in a casing 31. The protrusion 28 may bepunched directly from the bottom of the can if-desired.' In Fig. 5 the con- 'struction is identical'with that of 4 6X? cept that a pin 32 is inserted in the casing 31 instead. of being secured to the base of the container.

The modifications shown in Figs. 6 and 7 relate primarily to a vest pocket? type of battery in which three dry cells 5, 6 and 7 are placed along side each other and joined 1n series by *strips 33 connecting the zinc containers of 6 and 7 with the carbon electrodes of 5 and 6 respectively. One end of a flat spring 34 is soldered to the side of the zinc container of the dry cell 5 and engages the base of the lamp 12. The inclosed in an insulating case 35 having separating walls for the individual cells. A flat spring 36 is attached to the carbon electrode of the dry cell 7 and a seal. 37 is applied over the top of the dry cells as shown. The rheostat member 16 of the combination consists of an insulating casing 18 containing a plurality of resistance disks 1'9 retained by rims 25. At the base of the disks is placed a metal plate 37 soldered or otherwise fastened to the short end of a spring 38. When the rheostat is attached to the metal casing by means of screws for instance the projecting end of the spring 36 is adapted to yieldingly engage the long end of the spring 38 to make electrical connection between the battery and rheostat. A push button 38 is attached to a spring 39 which is riveted to the metal casing. By depressing the push button the circuit is closed through rheostat 16, plate 37, springs 38 and 36, dry

dry cells are consists of an insulating casing 31 containing resistance disks. Contact is made through an opening 30 of the casing 31 by means of push button 40 soldered to a spring 41 which is riveted to the casing 1. This arrangement differs from that of 6 only inv the position of the push buttton and manner of applying pressure to the rheostat.

In each of the modifications, it will, of course, be understood that it is not necessary to use a rheostat upon each dry cell, as in most instances one rheostat would be suflEL.

cient. Instead of using these carbon disks, I may use disks of other material or granular material may be used if desired.

While I have shown several waysof attaching the rheostat, and applying pressure thereto, it will be evident that other variations could be used and the invention is not limited to the examples given.

'Having described my invention, what I claim is:

1. The combination with a dry cell having zinc and carbon electrodes of an insulating tube attached to one end of the carbon electrode and ada ted to contain a plurality of conducting dis (s.

2. The combination with a dry cell having zinc and carbon electrodes of an insulating tube containing a plurality of carbon disks, said tube having openings at, each end, one opening being adapted to fit over said carbon electrode, and the other opening being adaptedto receive a contact for making electrical connection with an adjoining element anda seal for holding the tube on the carbon electrode. F

3. The combination in a flashlight of an outer casing, an insulating casing therein containing a dry cell having a projecting terminal, an incandescent lamp having. a

casing to compress ceive the projecting terminal at one end and the second terminal of the lamp at the other end, and a conducting cap having an inner pro ection adapted to be ad usted by means of threads upon said cab and conducting said button having a finger-piece'pi'ojecting casin' to c'o'm iress the disks-in said tube. outward through the opening in said cap.. 10

} 5. portab e electric lamp comprisinf a In testimony whereof, I hereunto aifix my tubular casing adapted to contain an e ecsignature in the presence of two witnesses. 5' tric lamp at one end, a cap attached to the MAJOR E. HOLMES.

opposite end, said ca formed with an open- Witnesses: ing, ands metal pus '-button within the cas- IRA J. AnAMs,

mg in which it is longitudinally movable, H. G. GRQVER. 

